The present invention relates to the manufacture of an inlaid article.
An inlaid article is normally manufactured by providing a recess or cavity adapted to receive therein an inlay or object made of a different material such that a design or other artistic relationship is obtained when the inlay is associated with the article. The article may be of a variety of shapes and sizes, and the problem of the prior art procedures is the ability to manufacture the article with the inlaid object perfectly matching the various contours of the recess in the article.
Since the article itself may be made of a hard and brittle material such as stone, glass, or semi-precious jewels, the ability to carve a recess in these hard and brittle materials and have the object or item to be inset therein matching with exacting peripheral contour has been a problem to date.
This problem has existed notwithstanding the fact that ultrasonic abrasive slurry machining, also known as ultrasonic impact grinding, has been in use for a considerable number of years and has been disclosed in U.S. Pat. No. 2,580,716, issued to L. Balamuth dated Jan. 1, 1952, entitled "Method and Means for Removing Material from a Solid Body" and is described also in Ultrasonic Engineering (book) by Julian R. Frederick, John Wiley & Sons, Inc., New York, NY (1966) pages 171 to 183.
The ultrasonic abrasive slurry machining process involves the use of an ultrasonically vibrating member having a tool which is in contact with or slightly spaced from a workpiece or article. Abrasive particles suspended in a fluid are fed into the gap between the tool and the article or workpiece and are driven with a percussive impact against the workpiece. The high velocity impact of the particles on the workpiece causes an abrading action which is used for producing accurate odd-shaped holes and recesses in hard materials. The abrasive slurry material used to perform the machining may be selected from a variety of materials well-known in the art, such as boron carbide, silicon carbide, or aluminum oxide, in a manner described in Ultrasonics (book) by Benson Carlin, McGraw-Hill Book Company, Inc., New York NY (1960), pages 285 to 288.
Accordingly, although the above process has been used for carving a recess on a variety of articles, there is a certain degree of wear for each carving and therefore the cross-sectional dimensions of each recess changes or varies from carving to carving. In a similar manner, the item or object to be inserted within the recess may be hand wrought, die struck, a casting, or acid etched. These manufacturing processes are similarly not exacting in that the peripheral contour of each object will also vary in shape.
Applicant has found that the machining with ultrasonic energy of a blank object into the article with the intention of thereafter positioning the desired object therein has proven to be inadequate in that in many instances the physical spacing or shape between the peripheral wall of the object and the inner wall of the recess do not properly match each other, due to variations in the object and/or variations in the carved recess, with resultant imperfections that are visible.